1. Field of the Invention
The present invention relates to a work-sheet holder feeding apparatus which is employed by a sewing machine including an elongate housing in which a loop catcher is accommodated.
2. Related Art Statement
Japanese Patent Application laid open for opposition under Publication No. 1(1989)-45394 discloses a work-sheet holder feeding apparatus which is employed by an industrial sewing machine for forming a sewing pattern or an embroidery pattern. The disclosed feeding apparatus includes right-hand and left-hand Y-direction feeding devices each of which includes a guide rail extending in a Y direction, and a support member which is movable in the Y direction by being guided by the guide rail; a movable frame which extends in an X direction perpendicular to the Y direction and which is supported at opposite end portions thereof by the respective movable support members of the two Y-direction feeding devices; a first drive motor which drives or rotates a drive shaft for moving the two support members in synchronism with each other in the Y direction and thereby feeding the movable frame in the Y direction; a rack which extends in the X direction and is fixed to a carriage which is supported on the movable frame such that the carriage is movable in the X direction; a spline shaft which extends in the Y direction independent of an elongate housing in which a loop catcher is accommodated; a pinion which fits on the spline shaft such that the pinion is movable in the Y direction relative to the shaft and which is engaged with the rack; and a second drive motor which is provided between the two Y-direction feeding devices and which drives or rotates the pinion. Thus, the carriage is movable not only in the X direction but also in the Y direction independent of the movement thereof in the X direction. Accordingly, a work sheet being held by a palette supported on the carriage is moved in the X and Y directions, so that a predetermined sewing pattern is formed on the work sheet.
In the above-described prior feeding apparatus, the left-hand and right-hand end portions of the movable frame, which supports the carriage, are driven or moved in the Y direction by the first drive motor via the left-hand and right-hand Y-direction feeding devices, respectively, and the carriage is moved by the second drive motor via the spline shaft, the rack, and the pinion. This arrangement is adopted for the purpose of reducing the weight of the movable frame.
However, there is a trend in the art toward the widening of a sewing area within which a sewing pattern is formed, and accordingly there is a trend toward the use of such a movable frame which has a greater dimension in the X direction and accordingly has a greater weight. In the case where such movable frame is employed and moved in the Y direction at a high sewing speed, the middle portion of the movable frame, which supports the carriage, may be moved with some delay as compared with the opposite end portions of the frame, that is, the movable frame may be curved in the Y direction.
Meanwhile, there is known a loop-catcher module or unit including a loop catcher, a drive shaft fixed to the loop catcher, and a drive source to drive or rotate the drive shaft of the loop catcher. In the case where the module is employed in the above-indicated prior feeding apparatus, the module may be accommodated in one of opposite end portions of the elongate housing. In this case, the remaining space in the housing remains vacant.
Furthermore, even in the case where a loop catcher is accommodated in an end portion of the elongate housing and is connected via a drive shaft to an external drive source which is not accommodated in the housing, some vacant space remains in the housing.